Over in Turkey at present and gas has just turned off onto petrol. Have stopped , cleared the code but just switches over to petrol again.
Fitted with a Prins Vsi system - more trouble than they are worth in my opinion.
I have had problems before - usually to do with the wiring but never this fault code before. Any ideas what it could be?

I'm no big fan of Prins but it might be a bit early to start blaming your Prins system, could be that the Prins system is refusing to run on gas because it has detected some problem with the car itself. I think that's unlikely though, given that you only mentioned a code for a canbus problem and haven't mentioned any P trouble codes (engine trouble codes) or engine misfires (misfire and loss of petrol injection pulse on cylinder(s) being one of the few vehicle problems that would make an LPG system refuse to run on gas).

So, having said the above (and in contrast to the above)... If it runs OK on petrol, still refuses to run on gas and you still get the U0009 code when running on petrol, then after checking the Prins diagnostics (separate to the vehicles OBD where you're seeing the U0009 code) to rule out simpler coincidences I'd probably expect to find some LPG associated wiring shorting to vehicle canbus wiring.. The thing is, though, such wiring problem could be anywhere there is LPG wiring and canbus wiring (under bonnet or inside the car, not forgetting VSI has about 7 wires running to the changeover switch and the ignition live might even be wired to inside the car instead of to petrol injector live under the bonnet). I'd probably start by looking at wiring near the engine ECU under the bonnet first, especially if the installer connected to petrol injector wiring near the petrol ECU, if I didn't find a problem there I'd follow the LPG switch wiring all the way to the switch inside the car, if the ignition live wire is connected inside the car I'd follow that wire all the way too.

Besides not running on LPG, do all your car's other functions (those likely connected to canbus) work such as the dash readings, climate control, central locking, etc?

Simon- thank you very much for this. It works fine on petrol and all the variables you mention are still functional. I have had wiring problems before with this install - usually accompanied by injector fault code. The terrain is very rough and bumpy here in Turkey and I reckon it could be relevant in this. Engine management light hasn't come on .
It is a Prins vs1 system fitted in the UK by approved installer. 2

Hello again Simon. Just been to the nearest Prins approved installer and he very quickly showed me faulty part + sheared wiring to no 3 injector. He said he could only do a repair as he only had sockets for Prins vs2 system - ( mine is 6 years old vs1 system).
Also showed me oxidised nuts on the injector rail- due to UK salty roads according to him!! I just have to go with the flow just now but I would like to come to you on my journey from Dover to Glasgow - around 12th December. I would like you to do a routine LPG service and a general look around to see if anything needs done. Would that be ok ?

The Prins diagnostics screen will have told him what was preventing the system running on gas (specifically detected problem with injector 3). I may have jumped the gun a bit assuming the U0009 appeared at the same time as the LPG system refused to work - Did the U0009 appear at the same time as the system refused to run on gas? Did he clear the U0009 and if so has it re-occurred?

What we can assume about oxidised nuts on say a Prins Kehin rail is that they wouldn't have oxidised if they weren't present because a different system had been fitted. A Prins installer but doesn't have any spare injector connectors for what is still the most common Prins system around..

I may be busy on 12th Dec, have an American motorhome coming for conversion on the 11th and will want to get a head start on that but I'd advise contacting me nearer the time, I may be OK to see you on the 12th.

LPGC wrote:The Prins diagnostics screen will have told him what was preventing the system running on gas (specifically detected problem with injector 3). I may have jumped the gun a bit assuming the U0009 appeared at the same time as the LPG system refused to work - Did the U0009 appear at the same time as the system refused to run on gas? Did he clear the U0009 and if so has it re-occurred?

What we can assume about oxidised nuts on say a Prins Kehin rail is that they wouldn't have oxidised if they weren't present because a different system had been fitted. A Prins installer but doesn't have any spare injector connectors for what is still the most common Prins system around..

I may be busy on 12th Dec, have an American motorhome coming for conversion on the 11th and will want to get a head start on that but I'd advise contacting me nearer the time, I may be OK to see you on the 12th.

Simon

Ok Simon. Too bad.
Ps 2 years ago I checked this installer out with Prins Netherlands and they confirmed that he was an approved installer with a very good reputation.
Interestingly he criticised the original install - which was done by Prins lead agent in the UK.
I was surprised though that they didn't have sockets for the old system. They say they only deal with Prins vs2 now.